The present invention is based on a method for correction of the detection range of a distance sensor which is not installed in the middle along the central axis, but at a lateral offset.
Distance sensors, in particular on the basis of a radar sensor or a lidar sensor, are used in the front of a motor vehicle in order to detect stationary or preceding and slower vehicles using a cruise control. The distance sensor detects in its detection range of approximately 150 meters and covers an angular range of approximately 10xc2x0. The ideal installation position for a sensor with such a narrow detection range is the center of the vehicle""s front. For technical and optical reasons, this area is not always available for installation, so that a position clearly outside the vehicle center must be used for the installation of the distance sensor. Due to the eccentricity, in addition to poorer coverage of one side in the short range, this results in a difference in the detection behavior, which can be sensed by the driver, in curves if this distance sensor is aligned parallel to the vehicle""s axis.
The method according to the present invention for correction of the detection range of a distance sensor which is installed with an eccentricity laterally offset with respect to the central axis of the motor vehicle has the advantage over the related art that the actual detection range is optimized so that it becomes approximately symmetrical with respect to the central axis of the motor vehicle. Thus better coverage is achieved, in particular in the short range, on the side which is farthest away from the site of installation of the distance sensor. It is considered particularly advantageous that, for example, when driving in a staggered convoy, the vehicle traveling behind can detect the vehicle traveling ahead better and more reliably.
It is particularly advantageous that the correction angle (aiming-off angle) is determined as a function of the eccentricity. For a greater eccentricity, the correction angle is selected to be greater than for a smaller eccentricity, so that optimum coverage of the lane, comparable to that in the case of installation in the center, is always guaranteed.
The correction angle can be determined advantageously and in a simple manner either empirically or with the help of a formula as a function of the minimum curve radius. This optimization method makes it then possible to optimize the detection range for the distance sensor, so that the difference with respect to a sensor installed in the center is as small as possible and the greatest possible detection range is covered, in particular even when traveling around a curve.
Since the correction angle is up to 1xc2x0 in practice, an adjustment of the distance sensor at the time of the installation is hardly noticeable optically, so that the design is not negatively affected.
The use of the distance sensor in connection with a cruise control system, so that the driver does not need to continuously monitor the safety distance taking into consideration the speed of travel, in particular when traveling in a convoy, is considered particularly advantageous.